Due to high breakdown electric field strength and high electron saturation velocity of silicon carbide (SiC), semiconductor devices based on SiC are provided for high temperature, high power and high frequency electronic semiconductor devices. High chemical stability of single crystalline SiC results in pure solubility in liquid etchants such that patterning of SiC surfaces for the formation of steps and trenches usually cannot rely on wet etching processes. Reactive ion etching, on the other hand, is highly anisotropic and typically results in comparatively rough surfaces and sharp-edged corners and steps. Heating treatments at temperatures above 1500° C. may smooth surface roughness and may round to some degree sharp-edged corners.
It is desirable to round or to chamfer steps as well as rims of trenches in semiconductor devices based on silicon carbide at less effort.